Your lock cylinder is broken. The anti-theft device in it thinks it was
being stolen and has broken off the coupling tab. This usually happens
when someone tries turning the key when the steering wheel is locked and
against one side of the locking cam.

Cure is a new lock cylinder - but I suspect since it's sitting outside
the "hardwear" (is that for steel clothing or something?) store - a tow
to a dealer should be in your near future plans.

BTDT. First, tighten the battery cables.